/** * @license Apache-2.0 * * Copyright (c) 2018 The Stdlib Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ 'use strict'; // MAIN // /** * Tests if a value is Node stream-like. * * @param {*} value - value to test * @returns {boolean} boolean indicating if a value is Node stream-like * * @example * var transformStream = require( '@stdlib/streams/node/transform' ); * * var stream = transformStream(); * * var bool = isNodeStreamLike( stream ); * // returns true * * bool = isNodeStreamLike( {} ); * // returns false */ function isNodeStreamLike( value ) { return ( // Must be an object: value !== null && typeof value === 'object' && // Should be an event emitter: typeof value.on === 'function' && typeof value.once === 'function' && typeof value.emit === 'function' && typeof value.addListener === 'function' && typeof value.removeListener === 'function' && typeof value.removeAllListeners === 'function' && // Should have a `pipe` method (Node streams inherit from `Stream`, including writable streams): typeof value.pipe === 'function' ); } // EXPORTS // module.exports = isNodeStreamLike;